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        // let arr = [4,7,5,3,4,5,7,4,2,4];
        // console.log(arr)
        //  let res =arr.indexOf(7)        
        //  let res=arr.indexOf(4,5)
        //  let res =arr.indexOf(7)        
        // console.log(res)
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    <script>
        // let arr =[4,8,9,2,6,7,1,3,5]
        // let res =arr.forEach(function(val){
        //     val *=2
        // console.log(val)
            
        // })
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    <script>
    var arr = [4,7,5,3,4,5];
     console.log(arr)
    var res = arr.map(function(val){
        console.log(val)
        return val * 1.3;
    })
    console.log(res) 
    console.log(arr === res);
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